Systems and methods for battery charger with internal power source

ABSTRACT

A battery charger with an internal power storage device may be used to facilitate fast charging of a battery by using a high C-rate. A battery charger with an internal power storage device may include a control circuit that receives operating mode instructions to operate in a base charging mode or a fast charging mode. In the base charging mode, the battery charger may be configured to concurrently charge a battery and an internal power storage device at a base C-rate using current supplied from an external power source. In the fast charging mode, the battery charger may be configured to charge the battery at a high C-rate, which is substantially higher than the base C-rate, by using the internal power storage device. The battery charger may include an optical reader used to identify battery-specific characteristics and enable the fast charging mode.

PRIORITY CLAIM

This application claims priority to U.S. Provisional Application Ser.Nos. 62/137,805, filed Mar. 24, 2015 and 62/163,148, filed May 18, 2015,which are expressly incorporated by reference herein.

BACKGROUND

Unless otherwise indicated herein, the description in this section isnot itself prior art to the claims and is not admitted to be prior artby inclusion in this section.

One aspect of a rechargeable battery is the battery's charge current.This charge current is often expressed in relation to a C-rate tonormalize against battery capacity because different batteries typicallyhave different capacities. A C-rate is a measure of the rate at which abattery may be charged by a battery charger relative to the battery'smaximum capacity. Batteries are made in a wide variety of chemistries,voltages, capacities, and charge rates. Battery chargers may be designedto work with a large number of available batteries.

Most conventional battery chargers charge typical rechargeable batteriesat C-rates in a range of about 1 C to 3 C. At a 1 C rate, a conventionalbattery charger will ideally charge a typical battery to substantiallyfull charge in about 1 hour. At a 3 C rate, a conventional batterycharger will ideally charge a typical battery to substantially fullcharge in about 20 minutes.

For example, a 1000 milliampere hours (mAh) battery charged at a 1 Crate can ideally be fully charged in about one hour with a conventionalbattery charger with a charging current of 1000 mA. Similarly, a 1000mAh battery charged at a 2 C rate can ideally be fully charged in about30 minutes with a conventional battery charger with a charging currentof 2000 mA, while a 1000 mAh battery charged at a 0.5 C rate wouldideally be fully charged in about 2 hours with a conventional batterycharger with a charging current of 500 mA.

SUMMARY

Recent advances in battery technology allow some batteries to be chargedfaster by applying more charge current to the battery. Some newbatteries may also be charged at much higher C-rates, such as at a 10 C(or higher) rate. For example, some types of advanced 1000 mAh batteriescan be charged at a 10 C rate, which can fully charge the battery in sixminutes with a battery charger configured to supply 10 amperes (“Amps”or “A”) of current at an appropriate voltage for the battery. Similarly,some advanced 1000 mAh batteries can be charged at a 30 C rate, whichcan fully charge the battery in 2 minutes with a battery chargerconfigured to supply 30 Amps at an appropriate voltage for the battery.

Most conventional battery chargers are not capable of charging batteriesat C-rates higher than about 1 C to 3 C due to various limitations. Forexample, both power and current limitations exist in standard householdcircuits where, typically, no more than about 1500 Watts (“W”) areavailable per circuit and each circuit's current is limited by ahousehold circuit breaker rated a particular current (e.g., a standard15A circuit breaker). In addition, most conventional battery chargersmust typically be electrically connected to an operating power supply tocharge a battery. Thus, charging at remote locations away from poweroutlets is difficult or impossible with a conventional charger that mustbe connected to an operating power supply via a wall socket or similarconnection. Another shortcoming of conventional battery chargers is thatthey typically require bulky additional equipment (such as AC-DCconverters or power supply adapters) that increases the difficulty ofcharging at locations away from power outlets.

Further complicating the process from a safety standpoint, theflexibility of modern battery chemistries allow some batteries to becharged more quickly than other, seemingly identical, batteries. C-rateis typically set by the battery manufacturer for specific battery modelsand may vary considerably between manufacturers of batteries of the sametype, voltage and capacity.

Charging a battery with incorrect parameters may result in seriousinjury to people and/or property damage in the area surrounding thecharging battery. For example, a battery charger that charges a batteryusing incorrect charging parameters may cause the battery to explode orcatch fire, thus injuring people or damaging property in the areasurrounding the battery. Battery charger manufacturers can mitigatecharging accidents that result in injury or property damage, e.g., bysimplifying the process of entering battery parameters into a batterycharger. To avoid accidents, it is critical that the battery parametersfor the charger are correctly matched to each battery being charged. Itis especially critical to correctly set parameters for a battery chargercapable of charging at high C-rates (e.g., 10-15 times higher than abase charge rate, such as a 3-C rate). For example, if a high C-ratecharging process were applied to a normal battery, the battery wouldlikely explode or catch fire due to being charged at an incompatiblyhigh C-rate. Similarly, a critical aspect of safety design for a batterycharger capable of charging batteries with high C-rates and high energydensities is how to ensure the battery charger applies the correctcharging parameters to each battery it is charging.

Battery charger manufacturers have attempted to solve these problemswith a model memory process or by using a magnetic stripe or RFIDprocess. For the model memory process, the battery charger requires auser to pre-program the battery charger with a limited quantity (e.g.,1-20) of battery model numbers and associated charging parameters.During subsequent operation, entering the battery model number into thecharger will then configure the charger with the previously programmedcharging parameters for a particular battery model.

For the magnetic stripe or RFID process, the manufacturer identifies thebattery and associated charging parameters with a code that is stored ona magnetic stripe or an RFID tag. During subsequent use, an RFID ormagnetic stripe reader on the charger reads charging parameters from theRFID tag or the magnetic stripe and configures itself according to thecharging parameters.

Drawbacks of using the existing model memory process include that theuser must first program the charger with the correct charging parametersassociated with an individual battery and for each subsequent chargecycle of the battery, must remember the battery model number associatedwith the battery. If the charge parameters are entered incorrectlyduring programming, or if the incorrect model number is entered into thecharger, the charger will incorrectly charge the battery, possiblyresulting in an explosion or fire. Drawbacks for the existing magneticstripe process include that the magnetic stripe is very susceptible todamage by even a weak magnetic field. Further, a magnetic stripe must beprogrammed by someone with a magnetic card writer (i.e., not a typicalconsumer), so this process is not reverse compatible with existingbatteries, or at least not easily accomplished with batteries that donot already have a magnetic stripe. Moreover, the amount of informationthat can be stored on the stripe is limited, similar to a conventionalbar code, to a few hundred bits of data. Likewise, the RFID tag can beaffected by electromagnetic fields (e.g., microwave ovens and securityinspection systems). The RFID tag process is also not reverse compatiblefor existing batteries because RFID tags can only be programmed by thebattery or charger manufacturer or someone with an RFID tag writer(i.e., not a typical consumer). Further, inexpensive RFID tags contain alimited amount of memory (e.g., 96-bit or 128-bit). This small amount ofdata is often not sufficient to store the necessary battery-specificcharging information and to encrypt some or all of the battery-specificcharging information. The model memory process and the magneticstripe/RFID processes are poorly suited to addressing the problem ofvariable charge rates and particularly ill-suited to very high currentcharging (e.g., high C-rate charging) with a secure (e.g., encryptable)method for activating the higher charge rates.

In view of the foregoing, a need exists for a new and improved batterycharger that can safely charge rechargeable batteries at (i) a baseC-rate (or base C-rate charging mode) and/or (ii) a high C-rate (or highC-rate charging mode) when connected to a conventional household circuitor in locations where conventional household circuits are not available.

In some embodiments, systems and methods related to battery chargers mayincorporate an internal power storage device (an internal power storagedevice may also be referred to throughout this specification as aninternal power source or an “IPS”). The battery charger may operate in(i) a base C-rate mode (or conventional mode) where the battery chargeris configured to charge one or more batteries at a base C-rate (orconventional C-rate), e.g., a C-rate of about 1 C to 3 C, and/or (ii) ahigh C-rate mode (or fast charge mode) where the battery charger isconfigured to charge one or more batteries at a high C-rate (e.g., aC-rate that is higher than the base C-rate, and in some casessubstantially higher than the base C-rate). For example, in someembodiments, the battery charger may be configured to charge one or morebatteries at a C-rate of about 7 C to 30 C when operating in the highC-rate mode.

As noted earlier, high C-rate charging may present difficulties due to,for example, power and current limitations of conventional householdcircuits. Beneficially, some embodiments described herein allow for highC-rate charging using a conventional household circuit. Some embodimentsmay additionally allow for high C-rate charging at a remote location(i.e., not connected to a household circuit). These as well as otheraspects, advantages, and alternatives will become apparent to those ofordinary skill in the art by reading the following detailed description,with reference where appropriate to the accompanying drawings.

A battery charger according to some embodiments of the disclosed systemsand methods includes (i) a power supply, (ii) a power storage device,and (iii) control circuitry. The control circuitry is configured toelectrically connect the power supply and the power storage device toone or more batteries for charging. In some embodiments, the controlcircuitry may also be (i) coupled to a user interface on or associatedwith the battery charger and (ii) configured to receive operating modeinstructions from the user interface. In operation, the operating modeinstructions indicate (i) a desired charging mode for the batterycharger, such as a base charging mode or a fast charging mode and/or(ii) particular charging parameters for a battery, including particularcharging parameters for base charging or fast charging. In someembodiments, the control circuitry is also configured to operate thebattery charger in the desired charging mode to charge one or morebatteries and/or to configure the charger with the particular chargingparameters.

In some embodiments, the power supply of the battery charger isconfigured to couple to an external power source, such as a conventionalhousehold circuit. While operating in the base charging mode, thebattery charger can concurrently charge both the power storage device ofthe battery charger and the one or more batteries at a base C-rate byusing current from the external power source. While operating in thefast charging mode, the battery charger can charge the battery using thepower storage device of the battery charger at a high C-rate, where thehigh C-rate is higher than the base C-rate, and in some instances,substantially higher than the base C-rate.

In some embodiments, the control circuitry is further configured tocontrol the charging rate of the battery charger when the batterycharger is operating in the high C-rate mode. In such embodiments, thebattery charger controls the charging rate in the high C-rate mode basedon battery characteristics. In some embodiments, the batterycharacteristics are received from the battery.

This overview is illustrative only and is not intended to be limiting.In addition to the illustrative aspects, embodiments, and featuresdescribed herein, further aspects, embodiments, and features will becomeapparent by reference to the figures and the following detaileddescription. The features and advantages of the disclosed systems andmethods, as well as other aspects, advantages, and alternatives willbecome apparent to those of ordinary skill in the art by reading thefollowing detailed description, with reference where appropriate to theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a simplified block diagram illustrating components ofa battery charger, according to an example embodiment.

FIG. 2 illustrates a simplified block diagram illustrating components ofa battery charger, according to an example embodiment.

DETAILED DESCRIPTION

Example methods and systems are described herein. It should beunderstood that the words “example,” “exemplary,” and “illustrative” areused herein to mean “serving as an example, instance, or illustration.”Any embodiment or feature described herein as being an “example,” being“exemplary,” or being “illustrative” is not necessarily to be construedas preferred or advantageous over other embodiments or features. Theexample embodiments described herein are not meant to be limiting. Itwill be readily understood that the aspects of the present disclosure,as generally described herein, and illustrated in the figures, can bearranged, substituted, combined, separated, and designed in a widevariety of different configurations, all of which are explicitlycontemplated herein.

I. Overview

Example embodiments relate to battery chargers, which may be used withvarious batteries for use in various systems, such as batteries forremote controlled vehicles or other devices which use rechargeablebatteries, e.g., flashlights, cameras, mobile phones, laptop computers,tablet computers, children's toys, remote controls, and music players.In particular, example embodiments may relate to or take the form ofmethods and systems for facilitating a high C-rate charge of one or morebatteries, including but not necessarily limited to batteries for usewith remote controlled vehicles. Example embodiments may include asafety component, such as an optical scanner that is either integratedinto the charger or otherwise in communication with the charger (e.g.,wirelessly connected via a smart phone). In contrast to previous systems(e.g., model memory or RFID systems), the battery charger system iscapable of storing, and possibly encrypting, the charging parametersand/or other information required to configure the battery charger tocharge the battery. For example, in embodiments where an optical scanneris the safety component, an optical code (e.g., a QR code) may be usedto store battery-specific information. The optical code may be placed ona battery (e.g., as part of a battery label) and the battery charger mayretrieve battery-specific information by scanning the battery label withthe optical scanner. Further, the optical code may be configured as asecure QR code, or encrypted QR code, such that the battery-specificinformation is encrypted. Use of an encrypted QR code may mitigatesafety risks. In some implementations, high C-rate charging or otherparameters are only enabled only after using the safety component toreceive and decrypt the encrypted battery-specific information. Amanufacturer may choose to not share the decryption process withconsumers in an effort to reduce charging errors and resulting damagesand/or injuries.

Most QR codes are capable of storing over 3 KB of data at very low cost,thus allowing all (or substantially all) battery-specific parameters tobe stored in a QR code on a battery label. The battery label may beplaced on the battery itself by the manufacturer or perhaps by theconsumer. The battery label may alternatively be displayed on a screen(e.g., on a computer screen or smart phone screen). As such, the batterylabel cost will be non-existent or extremely low cost, e.g., because thebattery labels may be displayed electronically. Alternatively, thebattery labels will be low cost because the labels may be printed onregular printer paper on a typical household printer. The batterycharger can then scan the optical code and receive the battery-specificcharging information.

In some embodiments, the battery charger may include one or moreprocessors, data storage, and program instructions (e.g., as part ofcontrol circuitry 110 discussed below). The one or more processors mayinclude one or more general-purpose processors and/or one or morespecial purpose processors (e.g., digital signal processors, applicationspecific integrated circuits, etc.). In operation, the one or moreprocessors are configured to execute computer-readable programinstructions that are stored in data storage and executable to provideat least part of the battery charger functionality described herein.

The data storage may include or take the form of one or morecomputer-readable storage media that may be read or accessed by the oneor more processors. The one or more computer-readable storage media mayinclude volatile and/or non-volatile storage components, such asoptical, magnetic, organic or other memory or data storage, which may beintegrated in whole or in part with at least one of the one or moreprocessors. In operation, the data storage may include computer-readableprogram instructions for operating the battery charger as well asperhaps additional data, such as diagnostic data relating to theoperation of the battery charger.

In some embodiments, the battery charger includes one or morecommunications interfaces. The one or more communications interfaces mayinclude wireless interfaces and/or wireline interfaces, which allow thebattery charger to communicate via one or more networks. In embodimentswith one or more wireless interfaces, the wireless interface(s) mayprovide for communication under one or more wireless communicationprotocols, such as Bluetooth, WiFi (e.g., an IEEE 802.11 protocol), aradio-frequency ID (RFID) protocol, near-field communication (NFC),and/or other wireless communication protocols, such as protocolsdesigned for use with radio controlled vehicles. In embodiments with oneor more wireline interfaces, the wireline interface(s) may include anEthernet interface, a Universal Serial Bus (USB) interface, or similarinterface to communicate via a wire, a twisted pair of wires, a coaxialcable, or other physical connection to a wireline network. Inembodiments with one or more communications interfaces, the batterycharger may communicate with batteries, other battery chargers, and/orother devices (e.g., a ground station of a remote controlled vehicle oran unmanned aerial vehicle) via the one or more communicationsinterfaces.

II. Illustrative Embodiments A. Battery Charger Example Components andBase Charging Mode

FIG. 1 depicts a simplified diagram of a battery charger 100 accordingto some embodiments. The battery charger 100 includes control circuitry110, link 111, user interface (“UI”) 120, IPS 130, power supply 140,battery charging circuitry 150, IPS charging circuitry 160, connectors170A and 170B, switches 180A and 180B, and terminals 181A, 181B, 182A,and 182B. FIG. 1 is representative only and not all components areshown. For example, additional electrical, structural, and/orrestraining components may not be shown.

Control circuitry controls the positioning of switches 180A and 180B tooperate the battery charger 100 in either the base mode or the fastcharge mode. When switch 180A is connected to terminal 181A and switch180B is connected to terminal 181B, the battery charger is operating inthe base mode. And when switch 180A is connected to terminal 182A andswitch 180B is connected to terminal 182B, the battery charger isoperating in the fast charge mode.

As shown in FIG. 1 and described more fully below, battery charger 100may operate in a base charging mode, where IPS 130 and a batteryconnected to battery charging circuitry 150 via connector 170B areconcurrently charged at a base C-rate by using a base current from thepower supply 140. Alternatively, the IPS 130 may be charged by IPScharging circuitry 160 using the base charging mode, regardless ofwhether a battery is connected and/or being charged.

Control circuitry 110 is coupled to a user interface 120. User interface120 may be a simple interface, such as a switch, or any other type ofinterface. For example, user interface 120 may include a touch screen,one or more LEDs, and/or a speaker. User interface 120 may also includea magnetic reader, a radio-frequency identification reader, and/or anoptical sensor and image processing circuitry. Alternatively or incombination, user interface 120 may include a software application thatinterfaces with a smartphone app, that configures the smartphone to actas a remote user interface with any of the user interface functionalitydescribed herein. In the embodiment shown in FIG. 1, control circuitry110 is electrically connected to the IPS 130, the power supply 140, thebattery charging circuitry 150, the IPS charging circuitry 160,connectors 170A and 170B, switches 180A and 180B, and battery 190.Depending on the configuration of the charger, some of these elementsmay be omitted or arranged differently than depicted in FIG. 1.

In operation, according to some embodiments, control circuitry 110 iscoupled to user interface 120 and is electrically connected to IPS 130,power supply 140, and a battery 190 connected to connector 170B. Controlcircuitry 110, battery charging circuitry 150, and/or IPS chargingcircuitry 160 may include power switches with high current ratings(e.g., 40 A or more). In some examples, control circuitry 110 and IPScharging circuitry 160 use power MOSFETs (metal-oxide-semiconductorfield-effect transistors) with high current ratings (e.g., 40A or more)that are at least sufficient to handle the current from IPS 130. In someembodiments, MOSFETs (such as n-channel MOSFETs and p-channel MOSFETs)may be used to implement logic gates and other digital circuits (e.g.,as switches 180A and 180B).

In some embodiments, the power supply 140 may be a switch mode powersupply. Due to possible operation in a wide variety of locations aroundthe world, the power supply 140 may need to accommodate many differentinput voltages. To accomplish this, in some embodiments, the powersupply 140 is a universal input voltage, high efficiencyalternating-current (“AC”) to direct-current (“DC”) switch mode powersupply. In such embodiments, the power supply 140 may include a switchmode power supply that can output 12 volts (“V”), 10 amperes (“A”), and120 watts (“W”) of regulated DC output from a power source that supplies100-240 V AC at a frequency of 50 or 60 Hertz (“Hz”).

In some embodiments, IPS charging circuitry 160 is a buck-boostconverter configured to utilize the “unused” capacity of the batterycharging circuitry 150. For example, if the battery charging circuitry150 is configured to output 120 W but is only using 100 W, IPS chargingcircuitry 160 can utilize the 20 W of “unused” capacity of power supply140 to recharge the IPS 130. In some embodiments, the IPS 130 isconfigured to supply up to 12-17 V, 40 A, and 700 W of unregulated DCoutput. In this example, the IPS 130 and battery charging circuit 150are capable of charging a 3 A battery at 13 C (39 A and 4.6 minutes) infast charge mode. Even higher C-rates may be accomplished by using IPS130 and battery charging circuitry 150 built with higher ampere ratedMOSFETs.

In some embodiments, IPS 130 is a low resistance, high capacity powerstorage device. For example, IPS 130 may include one or moreultra-capacitors, one or more super-capacitors, one or more electricdouble-layer capacitors, a battery, or another energy storage devicecapable of very high current delivery for multiple cycles. In operation,IPS 130 retains power once it is charged for a set period of time unlessit is discharged. For example, current lithium-ion polymer batteries aredesigned to retain power for at least 30 days and may be used alone orin combination with other components as the IPS 130. Thus, batterycharger 100 can be used in a different place or at a later time, afterIPS 130 has been charged.

Moreover, the capacity of the IPS 130 may be specifically designed for acertain set of batteries. In some embodiments, the battery charger 100is designed with an IPS 130 meant to base charge and fast chargebatteries intended to be used for aerial vehicles that use batteries inthe general range of 11.1 V to 22.2 V and 2,000 mAh-10,000 mAh capacity.For example, IPS 130 may be configured to charge an 11.1 V (i.e., 3cells of 3.7 volts connected in series in a single lithium-ion polymerbattery pack), 3000 mAh battery at a fast charge rate of 12 C (i.e.,fully charge in 5 minutes), and in such a configuration, the IPS 130includes a 14.8 V (i.e., 4 cells of 3.7 volts connected in series in asingle lithium-ion polymer battery pack) battery, capable of acontinuous discharge current of 36 A or more and a minimum capacity of3300 mAh.

An additional benefit of using a battery as the IPS 130 is that abattery can be easily replaced to overcome wear-out conditionsexperienced over the lifetime of the battery charger 100. In otherembodiments, the IPS 130 may include other power storage devices, suchas one or more capacitors, super-capacitors, graphene, or any other lowresistance, high capacity power storage device.

Because the IPS 130 and the battery 190 connected to battery chargingcircuit 150 and connector 170B may be charged over a period of time atthe base charging rate, power supply 140 can be smaller, more efficient,and lower cost than a conventional power supply that would be requiredto charge at the high C-rate of the fast charging mode. Moreover, powersupply 140 will more easily comply with noise emissions (e.g.,2004/108/EC, FCC 47 CFR radiated emissions, etc.) and electrical safetystandards (EN55014-2 for electrostatic discharge, radiatedsusceptibility, electrical fast transients, surge immunity, conductedsusceptibility, electromagnetic compatibility, etc.) than conventionalpower supplies configured to charge batteries at similar high C-rates.

In practice, battery charger 100 may be installed in a workshop,vehicle, or other location. In this example, connectors 170A allow powersupply 140 to be either external to the battery charger 100 orintegrated within battery charger 100. Of course, in other embodiments,the battery charger 100 may be configured to not include power supply140, but rather to connect to an external power supply due to weight,cost, size, or other constraints. In such examples, control circuitry110 may be electrically connected to power connectors 170A, which inturn connect to (an external) power supply 140.

In some embodiments, an external power supply 140 may be disconnectedfrom battery charger 100 after IPS 130 has been fully charged. IPS 130can then provide all power to battery charging circuit 150 and a batteryconnected to 170B can be charged at base C-rate current or high C-ratecurrent charging levels.

In some embodiments, control circuitry 110 is configured to receiveoperating mode instructions and/or battery-specific charging data fromuser interface 120 and/or control circuitry 110 (e.g., via an opticalsensor or other safety component). Operating mode instructions mayinclude instructions on whether the charger should operate at (i) abase, or conventional, charging mode using a base C-rate (such as 1 C to3 C) for charging the battery or (ii) at a fast operating mode using ahigh C-rate (such as 10 C to 30 C) for charging the battery. Forexample, user interface 120 may be a two-position switch or toggle whoseposition indicates the desired operating mode. The C-rates may bereceived from user interface 120 or may be determined, for example, bythe characteristics of the battery to be charged by the charger.Moreover, the C-rates may be variable. For example, the C-rates may varybased on a battery characteristic, such as a temperature rating, or anoperational condition of the battery, such as a battery temperature(e.g., the battery temperature may be sensed by a temperature sensorinstalled in, or added to, a battery). The C-rates may also vary if thecharger is configured to charge different batteries with varyingcharacteristics or by user input (e.g., from user input at the userinterface 120, such as touch input where user interface 120 is atouchscreen). Battery-specific charging data (or battery chargingcharacteristics) may include information related to the specific batteryto be charged, such as its C-rate, voltage rating, current rating,capacity, chemistry (e.g., Li—Po or NiMH), and/or other battery andcharging characteristics.

In some embodiments, when in the base charging mode, the charger isconfigured to concurrently charge the battery and the IPS 130 at thebase C-rate by using current (or “unused” capacity) from power supply140 as described herein, and when in the fast charging mode, the chargeris configured charge the battery using the IPS 130 at a high C-rate.

In some embodiments, battery charger 100 includes battery chargingcircuitry 150 that is electrically connected to control circuitry 110and the battery to be charged. In operation, battery charging circuitry150 is configured to limit one or more battery charging characteristicsfor the battery to improve safety and reliability of battery charger100. In some embodiments, battery charging circuitry 150 may comprise abattery management system. For example, battery charging circuitry 150may prevent, or at least reduce the likelihood that, charging thebattery will cause situations such as over-current, over-charging,under-voltage, over-temperature, over-pressure, cell imbalance, and/orground fault. In some embodiments, instead of separate battery chargingcircuitry 150, control circuitry 110 may be configured to perform thefunctions of the battery charging circuitry 150.

In some embodiments, battery charger 100 includes IPS charging circuitry160 that is electrically connected to control circuitry 110 and IPS 130.In operation, IPS charging circuitry 160 is configured to limit one ormore IPS charging characteristics to improve safety and reliability ofthe battery charger 100. In some embodiments, IPS charging circuitry 160may comprise a battery management system. IPS charging circuitry 160 mayprevent, or at least reduce the likelihood that, charging the IPS willcause situations such as over-current, over-charging, under-voltage,over-temperature, over-pressure, cell imbalance, and/or ground fault.Instead of separate IPS charging circuitry 160, control circuitry 110may be configured to perform the functions of the IPS charging circuitry160.

In some embodiments, control circuitry 110 receives batterycharacteristics data (or battery characteristics input), e.g., from userinterface 120 or some other component, such as an optical reader. Forexample, battery characteristics input may include battery capacity,battery voltage, temperature (e.g., cut-off temperature or maximumrecommended temperature), battery chemistry, or cell configuration.Alternatively, control circuitry 110 may receive battery characteristicsinput from the battery. If control circuitry 110 receives input from thebattery, real-time input may be provided, such as real-time temperatureand charging progress. As used throughout the specification,battery-specific charging data may include battery chargingcharacteristics, battery characteristics input, and/or any other datarelated to charging a battery (e.g., connector type, dimensions, etc.).

B. Battery Charger Fast Charging Mode

As described herein, battery charger 100 operates in fast charge modewhen switch 180A is connected to terminal 182A and switch 180B isconnected to terminal 182B. In a similar manner, one or more MOSFETswitches (e.g., an n-channel MOSFET) may be used to switch batterycharger 100 into (and out of) fast charging mode. Although batterycharger 100 is described as utilizing both a base charging mode and afast charging mode, battery charger 100 may also be configured such thatit only charges batteries in a fast charging mode or base charging mode.

As shown in FIG. 1, in fast charging mode, current flows from IPS 130 tothe battery (e.g., through battery charging circuitry 150 and batteryconnector 170B) at a high C-rate. In this embodiment, control circuitry110 receives or identifies battery characteristics (e.g., how muchcurrent can be safely provided to the battery). Control circuitry 110may receive battery characteristics in a number of ways, including,without limitation: (i) by the shape of the battery acting as amechanical key, (ii) through use of an optical scanner (e.g., QR codescanner or barcode scanner), (iii) by the battery charger includingmultiple connectors, each of which connect only to certain types ofbatteries, and/or (iv) from the battery which may couple to controlcircuitry 110, e.g., through the optional communication link 111 shownin FIG. 1. In response to receiving the battery characteristics, controlcircuitry 110 may optimally adjust the C-rate, current flow, voltage, orother charging parameters.

FIG. 2 illustrates a simplified circuit diagram illustrating componentsof a battery charger 200, according to an example embodiment. Batterycharger 200 includes a power switch 202, a circuit breaker 204, a filter206, an AC/DC switch mode power supply 208, a microprocessor 210, fans212, one or more safety and user interface components 214, a batterycharger module interface 220, an internal power source (IPS) 230, IPScharging circuitry 240, a power path selector 250, current sensingcircuitry 260, MOSFETs 270, and a battery charger module 280. FIG. 2 isrepresentative only and not all components are shown. For example,additional electrical, structural, and/or restraining components may notbe shown. In some embodiments, elements of FIG. 2 may be omitted. Forexample, battery charger module 280 may be included as part of batterycharger 200 or may be a separate component from battery charger 200. Forpurposes of this application, a battery charger 200 mode that operatesthe charger to charge at a high C-rate (e.g., over 3 C) may be referredto as a fast charge mode, a High-C charge mode, and/or a “HC” mode.

In operation, in some embodiments, battery charger 200 may be pluggedinto a variety of AC voltage sources, for example, ranging from 100 V to240 V with frequencies of 50 Hz to 60 Hz. Power passes from the AC inputthrough a power switch 202, e.g., a user activated, ON/OFF rocker switchand a circuit breaker 204. Circuit breaker 204 may have resetfunctionality, such as a push button reset. Power then passes through afilter 206, such as an electromagnetic filter (e.g., a single line EMIfilter or a power line filter) to reduce electromagnetic emissions andelectrostatic discharge susceptibility.

Battery charger 200 may also include a Switch Mode Power Supply (SMPS)208 (e.g., an AC/DC SMPS) where power is rectified to DC and regulatedby circuitry that will maintain a specific output voltage (such as 12 VDC) with a specific maximum output rating (such as 10 A (120 W)). Otheroutput voltages and power levels may be chosen for specificapplications. The SMPS 208 may monitor its output to detect any sign ofcurrent draw exceeding the operational limit of the supply (i.e., anOver Current Fault) and, to prevent damage, will shut down the batterycharger 200. A signal indicating an Over Current Fault will be passed tothe microprocessor 210 if this occurs. The microprocessor 210 may thenset appropriate output status signals, such as changing the status ofthe battery charger module interface 220. As illustrated in FIG. 2, themicroprocessor 210 may light LEDS using battery charger module interface220 to indicate an Over Current Fault.

To monitor the thermal performance of battery charger 200, temperaturesensors, (illustrated in FIG. 2 as temperature sensors T1 and T2) may beconnected to the microprocessor 210. For example, T1 and T2 may beattached to heat sinks (not shown) of the battery charger 200 to allowthe microprocessor to monitor the thermal performance of the system andadjust the speed of the cooling fans 212 as necessary.

Current sensors are used to allow the battery charger 200 to monitorreal time current output of the SMPS 208 and the IPS 230. Examples ofcurrent sensors include digital/inductive current sensors, closed loopcurrent sensors, and open loop current sensors. As illustrated in FIG.2, current sensors 260 are configured to monitor the real time currentoutput of SMPS 208 and the IPS 230. In the event that power drawn by thebattery charger 200 is less than the output limit (e.g., 120 W) of theSPMS 208, the charging circuit 240 may utilize the “unused”, orremaining, power up to the output limit (e.g., up to the 120 W limit) tocharge the IPS 230. When the charging circuit 240 is active, themicroprocessor 210 may set appropriate output status signals includingHC Charging (illustrated in FIG. 2 by LED2 of battery charger moduleinterface 220).

Similarly, if the voltages of any of the IPS 230 storage elements arebelow a minimum level, the microprocessor 210 may set appropriate outputstatus signals at the battery charger module interface 220, such aslighting LED3 (or changing a graphical user interface such as an LCD) toindicate the depletion of the IPS 230 (illustrated in FIG. 2 as HCDepleted). In some embodiments, when the IPS 230 is below a minimumlevel (e.g., when the HC Depleted signal is active), HC mode may beprohibited such that the battery charger 200 is limited to theconventional charging operation (e.g., 10 A and 120 W).

In some embodiments, battery charger 200 may receive batterycharacteristics in a number of ways, including, without limitation: (i)by the shape of the battery acting as a mechanical key, (ii) through useof an optical scanner (e.g., QR code or barcode), (iii) by the batterycharger including multiple connectors, each of which connect only tocertain types of batteries, and/or (iv) directly from the battery. Inresponse to receiving the battery characteristics, control circuitry 110may optimally adjust the C-rate, current flow, voltage, and/or othercharging parameters.

In embodiments where an optical scanner is used, the microprocessor 210may monitor for input from an Optical Code Recognition (OCR) module. Insome embodiments, a safety component 214 may be an OCR module such as aBluetooth-enabled smartphone that includes an integrated camera. Asillustrated in FIG. 2, safety and user interface components 214 mayinclude an OCR module directly connected to the battery charger 200 (orintegrated within battery charger 200). For example, an Inter-IntegratedCircuit (I²C) communication protocol may be used to connect an OCRmodule to the microprocessor 210. Alternatively or additionally, batterycharger 200 may include wireless functionality to connect to an OCRModule (e.g., a smart phone with a camera may use a Bluetooth connectionto wirelessly connect to the battery charger). As illustrated in FIG. 2,the microprocessor 210 is connected to a Bluetooth-enabled chipset suchthat wireless communication via the Bluetooth protocol may be used tocommunication with an OCR module 214. Other wireless protocols may beused as well.

The purpose of the OCR module 214 is to scan an optical code. Theoptical code may be printed on, or attached to, a battery or may bedisplayed on an interface (e.g., a graphical interface of a smartphone).The optical code may be implemented in a conventional form such as a QRcode or in a custom label format.

The optical code may contain information related to the characteristicsof a specific battery or characteristics necessary to charge a specificbattery, including, but not limited to: battery chemistry, batterycapacity, cell count (voltage), standard charge rate (C) and whether thebattery is compatible with fast charge mode or HC mode. In someembodiments, compatibility with HC mode may be represented by batterycharacteristics as a 1 or 0, such that a value of 1 indicates thebattery is compatible with HC mode and a value of 0 indicates thebattery is not compatible with HC mode. In some embodiments,compatibility with HC mode may be encrypted within the batterycharacteristics but not specifically identified by a unique functionidentifier such as a 1 or 0. In addition, the encrypted data may requirea Cyclic Redundancy Check (CRC) code (or other error checking mechanism)to prevent the misuse of encrypted HC mode data to activate HC mode whenthe battery charger 200 is charging conventional (1 C-rate) batteries.

In some embodiments, HC mode may be prohibited unless the batterycharger determines that the battery characteristics of the battery to becharged are safe to charge in HC mode. For example, if the OCR module214 returns that the battery is compatible with HC mode (and there issufficient capacity in the IPS 230), the microprocessor 208 may directthe Power Path Selector 250 to switch the IPS 230 into the circuit andallow the battery charger 200 to draw up to the maximum rated outputpower (e.g., 40 A and 700 W) of the IPS 230. In some embodiments, themicroprocessor 208 will activate the HC Active output once the IPS 230is online (e.g., LED1 of battery charger module interface 220 may beactive as illustrated in FIG. 2).

As battery charging continues, the microprocessor 208 may monitor theoutput current draws (e.g., via current sensors 260). If at any time thecurrent draw goes below the output rating of the SMPS 208, themicroprocessor 208 may be configured to switch the IPS 230 back out ofthe circuit and allow the battery charger 200 to draw power from onlythe SMPS 208. Once the IPS 230 is offline, the microprocessor 208 mayturn off the indication on the user interface 220 of HC Active (e.g.,LED1 may be deactivated). The microprocessor 210 may be furtherconfigured to further monitor the current draw and direct the power pathselector 250 to switch the IPS 230 back into the circuit if the currentdraw increases to a level of 10A or greater.

As discussed previously, when power drawn by the battery charger 200 isless than the output limit of the SMPS 208, the charging circuit 240 mayuse all remaining power (up to the output limit) to charge the IPS 230.It may be beneficial for the battery charger 200 to use the SMPS 208 toprovide as much of the power required to charge the battery as possible,up to its rated output (e.g., 10 A, 120 W). In some embodiments, thereserve capacity of the IPS 230 may be limited to peak demand,effectively “duty cycling” the IPS 230 to make effective use of itspower reserves, to extend the number of Hyper Charge cycles, and tolimit down time.

As illustrated in FIG. 2, the output of the SMPS 208 is connected toNMOS switches 270. In the example shown in FIG. 2, charging circuit 240is a buck boost, lithium-ion discrete charger, implemented as a constantcurrent, constant voltage (CI/CV) converter. In operation, the CI/CVconverter of the charging circuit 240 will run in constant current modeto charge the IPS 230 to a predetermined level, and then switch toconstant voltage mode to maintain the charge of the IPS 230. Thecharging circuit 240 may switch dynamically between these modes on thefly with no intervention of the microprocessor 208.

The charging circuit 240 may have an analog current limit input whichwill limit the current utilized by the charging circuit 240 to a levelbetween 0 A and 10 A of input current. The power path from the SMPS 208may include a current sense element and an instrumentation amplifier(not shown) with resistor settable gain, which will output a value ofavailable capacity to the charging circuit 240 to prevent the chargingcircuit 240 from overloading the SMPS 208.

In a further aspect, the analog current limit allows the IPS 230charging current to be adjusted continuously based upon the consumptionof the power path between the SMPS 208 and the battery (e.g., duringconventional charging when the IPS 230 is not being used). As thecurrent needs fluctuate on the power path between the SMPS 208 and thebattery that is being charged, the charging circuit 240 may utilize allexcess capacity of the SMPS 208.

C. Additional Features

In some embodiments, the battery charger may further include anintegrated optical code reader. For example, the battery charger 200 mayinclude a safety component 214 such as an optical character recognition(“OCR”) module. The OCR module may be a combination of image processingcircuitry and an image sensor (e.g., a laser scanner, a CCD array, aCMOS sensor, a digital camera, a QR code scanner, a internal powersourcebarcode scanner).

The optical reader equipped charger may have various modes of operation.For example, the battery charger 200 may operate in a conventional modewith any battery using the traditional interface controls (e.g., to setcharge rate, voltage, current, etc.). In another mode, the batterycharger 200 may operate in a rapid entry mode where some chargingparameters may be entered via the safety component 214 (e.g., a QR codescanner). Those charging parameters (and possibly other parameters) canthen be verified and/or modified by a user prior the start of thecharging cycle using the user interface 220. In another mode, allcharging parameters may be entered via the safety component 214 (e.g., aQR code scanner). Those charging parameters may then be verified by theuser (e.g., via the user interface 220) without the possibility ofmodification before the start of the charging cycle. Of course, a cancelor abort option may be available at any time.

To support this type of charging, a software program can be provided tousers allowing them to generate inexpensive code labels (e.g., a QR codegenerator designed to be used with a personal computer and a standardhousehold printer and paper or perhaps with adhesive labels) to be usedin older style batteries that are not capable of charging at a highC-rate. The software program may restrict the QR codes such thatcharging parameters for C-rates cannot be changed or cannot be set abovea threshold value (e.g., 1-C) to reduce the likelihood of accidents andmisuse.

Advantages of this system include, without limitation, compatibilitywith virtually all existing batteries, improved ease of use, reducedlikelihood of user programming error, and low unit cost batteryidentifiers (i.e., multiple identifiers could be printed on a standardpiece of paper or on a single sheet of preconfigured adhesive labels).

Similarly, a battery charger with an integrated safety component (e.g.,an optical code reader such as a QR code reader) may have various modesof operation. In one mode of operation, the battery charger 200 mayoperate in a conventional manner with any battery using the userinterface 220 controls. In this mode, no high C-rate charging is enabledfor safety purposes.

In another mode of operation, the battery charger 200 may operate in arapid entry mode where many charging parameters are rapidly entered viathe safety component 214. For example, the safety component 214 may be aQR code scanner which may scan a QR code on a battery to be charged. TheQR code may contain multiple charging parameters which themicroprocessor 210 may use to set the charging circuitry 240 to safelyoperate the battery charger 200. The charging parameters may be verifiedand/or modified (e.g., via a switch, button, touchpad, or other inputdevice on user interface 220) by the user. In some embodiments, userinput for verification may be provided in the form of verification dataat the user interface 220 such as data indicating a switch positionbeing flipped, a button press, a touch input, etc. In this rapid entrymode, high C-rate charging is not allowed. For example, themicroprocessor 210 may limit the battery charger 200 to below a maximumC-rate threshold (e.g., 1-C).

In another mode of operation, the battery charger may operate in a fastcharge mode (or a high C-rate mode). For example, the battery charger200 may receive direct entry of battery-specific charging parameters,e.g., from the safety component 214. In some embodiments, the batterycharger 200 may have a safety component 214 that is a QR code scanner.The battery charger 200 may use the QR code scanner to scan a QR codefor a compatible high C-rate battery, set the charging parameters forbattery-specific charging parameters, and operate to safely charge thebattery at a high C-rate that will not damage the battery. In this mode,verification of the charging parameters may occur (e.g., via 220) but nomodifications of the charging parameters are allowed. However, thecharging may always be cancelled or aborted, e.g., via battery chargermodule interface 220.

Software may be used to generate code labels for these modes asdescribed above. In some embodiments, the software may not allowconsumers to generate code labels (e.g., QR codes) that include C-ratedata. This may reduce the likelihood of misuse of the high C-ratecharging mode and may reduce the number and likelihood of accidents,injuries, and damage. For example, the manufacturer may choose toencrypt the battery-specific code as it relates to C-rate data (or othercharging parameters). This encryption may be accomplished in many ways.For example, a QR code (or parts of a QR code) may be encrypted via aData Encryption Standard (DES) encryption process, Triple DES process,Advanced Encryption Standard (AES) process, or other encryption process.

In some embodiments, compatibility with high C-rate charging mode may beencrypted within the battery-specific data but not specificallyidentified by a unique function identifier such as a 1 or 0. Inaddition, the encrypted data may require a Cyclic Redundancy Check (CRC)code (or other error checking mechanism) to prevent the misuse ofencrypted HC mode data to activate HC mode when the battery charger 200is charging conventional (1 C-rate) batteries.

Advantages of operation in previously described modes include, withoutlimitation, compatibility with virtually all existing batteries,compatibility with new high C-rate charging batteries, encryption ofcharging parameters (such as the charge rate parameter for safetypurposes) to prevent misuse, improved ease of use, reduced likelihood ofuser programming error, and low unit cost battery identifiers.

In some embodiments, a low cost battery charger 200 may include a safetycomponent 214 in the form of an optical reader and may remove all userinterface options except a simple switch (e.g., a two-position switchrepresenting Start/Stop functions to activate or deactivate a chargingcycle). This type of low cost charger is possible due to the use of theintegrated optical scanning system providing the control circuitry withsufficient data for charging parameters such that the battery chargercan safely charge the battery.

The size of the power supply, the use of an internal or external powersupply and the capacity of the internal power source (as well asaccompanying circuitry) can be scaled to best suit various ranges ofbatteries.

D. Conclusion

The above detailed description describes various features and functionsof the disclosed systems, devices, and methods with reference to theaccompanying figures. In the figures, similar symbols typically identifysimilar components, unless context dictates otherwise. The exampleimplementations described herein and in the figures are not meant to belimiting. Other implementations can be utilized, and other changes canbe made, without departing from the spirit or scope of the subjectmatter presented herein. It will be readily understood that the aspectsof the present disclosure, as generally described herein, andillustrated in the figures, can be arranged, substituted, combined,separated, and designed in a wide variety of different configurations,all of which are explicitly contemplated herein.

The particular arrangements shown in the figures should not be viewed aslimiting. It should be understood that other implementations can includemore or less of each element shown in a given figure. Further, some ofthe illustrated elements can be combined or omitted. Yet further, anexample implementation can include elements that are not illustrated inthe figures.

While various aspects and implementations have been disclosed herein,other aspects and implementations will be apparent to those skilled inthe art. The various aspects and implementations disclosed herein arefor purposes of illustration and are not intended to be limiting, withthe true scope being indicated by the following claims.

We claim:
 1. A battery charger, comprising: control circuitry configuredto electrically connect to (i) a power supply, (ii) an internal powersource, and (iii) a battery, a safety component coupled to the controlcircuitry and configured to provide battery-specific charging data tothe control circuitry; wherein the control circuitry is configured tooperate the battery charger in at least two modes: (i) a base chargingmode and (ii) a fast charging mode; wherein in the base charging mode,the battery charger is configured to concurrently charge (i) the batteryat a base C-rate by using current from the power supply and (ii) theinternal power source at the base C-rate by using current from the powersupply; and wherein in the fast charging mode, the battery charger isconfigured to charge the battery using the internal power source at ahigh C-rate, and wherein the high C-rate is higher than the base C-rate;wherein the control circuitry is configured to enable the fast chargingmode in response to receiving battery-specific data from the safetycomponent indicating the battery is capable of handling charging at thehigh C-rate.
 2. The battery charger of claim 1, further comprising abattery charging circuit, wherein the battery charging circuit iselectrically connected between the control circuitry and the battery;and wherein the battery charging circuit is configured to limit abattery charging characteristic.
 3. The battery charger of claim 2,further comprising an internal power source charging circuit, whereinthe internal power source charging circuit is electrically connectedbetween the power supply and the internal power source; and wherein theinternal power source charging circuit is configured to limit aninternal power source charging characteristic.
 4. The battery charger ofclaim 3, wherein battery-specific data includes battery characteristicsdata and the control circuitry is further configured to limit, based atleast in part on the battery-specific charging data, a battery chargingcharacteristic.
 5. The battery charger of claim 4, wherein the batterycharacteristics data includes C-rate and at least one of (i) batterycapacity, (ii) battery voltage, (iii) temperature, (iv) batterychemistry, and (v) cell configuration.
 6. The battery charger of claim3, wherein the internal power source charging characteristic comprisesone or more of (i) over-current, (ii) over-voltage, (iii) under-voltage,(iv), over-temperature, (v) over-pressure, and (vi) ground fault.
 7. Thebattery charger of claim 2, wherein the battery charging characteristiccomprises one or more of (i) over-current, (ii) over-voltage, (iii)under-voltage, (iv), over-temperature, (v) over-pressure, and (vi)ground fault.
 8. The battery charger of claim 1, wherein the safetycomponent is an optical sensing device; and wherein the battery chargerfurther comprises image processing circuitry connected to the controlcircuitry; and wherein the control circuitry is further configured to:receive an image from the optical sensing device; and detectbattery-specific data from the image with the image processingcircuitry.
 9. The battery charger of claim 8, wherein the opticalsensing device is (i) a laser scanner, (ii) a CCD array, (iii) a digitalcamera, (iv) a QR code scanner, or (v) a barcode scanner.
 10. Thebattery charger of claim 8, wherein the battery-specific data isencrypted.
 11. A battery charger, comprising: a power supply connectorconfigured to connect the battery charger to an external power supply; aconnector configured to connect the battery charger to a battery; aninternal power source; a set of one or more switches configured toswitch the battery charger between a plurality of operating modescomprising: (i) a base C-rate charging mode where the battery chargersupplies power, from the external power supply at a base C-rate, to thebattery and the internal power source and (ii) a high C-rate chargingmode where the battery charger supplies power at a high C-rate from theinternal power source to the battery, wherein the high C-rate is higherthan the base C-rate; and control circuitry configured to switch thebattery charger to the high C-rate charging mode only after receiving anindication that a battery connected to the connector is capable ofreceiving power at the high C-rate.
 12. The battery charger of claim 11,further comprising image processing circuitry connected to the controlcircuitry, wherein the control circuitry is further configured to:receive the indication from an image sensed by an optical sensingdevice; and detect battery-specific data from the image with the imageprocessing circuitry.
 13. The battery charger of claim 12, wherein theoptical sensing device is (i) a laser scanner, (ii) a CCD array, (iii) adigital camera, (iv) a QR code scanner, or (v) a barcode scanner. 14.The battery charger of claim 12, wherein the battery-specific data isencrypted.
 15. The battery charger of claim 14, wherein the controlcircuitry is configured to limit a battery charging characteristic andis configured to limit an internal power source charging characteristic.16. The battery charger of claim 11, wherein the base C-rate is lessthan or equal to 3 C and the high C-rate is greater than or equal to 5C.
 17. The battery charger of claim 11, wherein the internal powersource is a battery, a capacitor, a super-capacitor, or a grapheneenergy storage device.